In the case of entirely metal turbine ring assemblies, it is necessary to cool all of the elements of the assembly and in particular the turbine ring which is subjected to the hottest flows. This cooling has a significant impact on the performance of the engine since the cooling flow used is taken from the main flow of the engine. Furthermore, the use of metal for the turbine ring limits the possibilities of increasing the temperature at the turbine, although this would make it possible to improve the performance of aeronautical engines.
In an attempt to solve these problems, it has been envisioned to produce turbine ring sectors from ceramic matrix composite (CMC) material in order to do away with the use of a metal material.
CMC materials have good mechanical properties, making them able to form structural elements, and beneficially retain these properties at high temperatures. The use of CMC materials has beneficially made it possible to reduce the cooling flow to be imposed during operation and thus to enhance the performance of the turbomachines. Furthermore, the use of CMC materials makes it possible beneficially to reduce the mass of the turbomachines and to reduce the heat expansion effect encountered with metal parts.
However, the existing solutions proposed can employ an assembly of a CMC ring sector with metal attachment parts of a ring support structure, these attachment parts being subjected to the hot flow. Consequently, these metal attachment parts undergo heat expansion, and this can result in the CMC ring sectors being mechanically stressed and weakened.
Furthermore, the documents FR 2 540 939, GB 2 480 766, EP 1 350 927, US 2014/0271145, US 2012/082540 and FR 2 955 898, which disclose turbine ring assemblies, are known.
There is a need to improve the existing turbine ring assemblies and the mounting thereof, and notably the existing turbine ring assemblies that use a CMC material, in order to reduce the intensity of the mechanical stresses to which the CMC ring sectors are subjected during operation of the turbine.